Numerous communication systems support very high speed data rates. For example, many practical digital communication systems process data at speeds of up to 40 Gb/s. Practical high speed data communication systems employ a number of interconnected elements such as electronic devices, components, modules, circuit boards, subassemblies, and the like. High speed clock/data inputs and outputs of such elements require interconnection at the subsystem and system levels.
There are a limited number of interconnects that can be used for very high speed data communications. Connectors are often used for the interconnection of signal paths. Such connectors often are bulky, require difficult cable layouts and require specialized component packages and may introduce discontinuities in the signal path.
The present FR-4 printed circuit boards (PCBs) are strong and are commonly used today. However, FR-4 PCBs include connectors but are not good at conducting high frequency electrical signals. This is because they have a loss of signal strength and a distortion of pulse shape of pulses in the electrical signals depending on the path and the length that traces on the board. The loss of signal strength and distortion can be attributed in part to the location of the connector away from the signal path. For example, an output driver chip may be electrically connected to a PCB and the signals it receives and sends may suffer a loss of signal strength and distortion when the signals have to be routed over long distances and/or through the board to get to the connector. Thus, many PCBs layouts are designed to reduce those long distances so that the output driver chips are close to the connector.
Furthermore, other factors may determine the output driver chip be put some distance from the output connector on the back/side/edge of a mobile phone, TV, projector, etc. Various solutions have been proposed in the prior art that include the use of a more expensive PCB material, use of more layers, or reworking the board to place critical components closer together.